Acupuncture for post-operative cognitive dysfunction: a systematic review and meta-analysis of randomized controlled trials

An overview of systematic reviews of acupuncture for neurodegenerative disease

BACKGROUND

Acupuncture has been widely used in the treatment of neurodegenerative diseases and a large number of systematic reviews (SRs) have been published, but the results are controversial. Therefore, it is necessary to comprehensively summarize and objectively evaluate the clinical evidence of acupuncture for neurodegenerative diseases.

OBJECTIVE

To evaluate the SRs that assess the efficacy and safety of acupuncture for neurodegenerative diseases. This overview is intended to provide evidence for clinical decision making by healthcare providers and policymakers and to provide evidence for clinical decision making by healthcare providers and policymakers and to provide recommendations for researchers to conduct high quality SRs and clinical studies.

METHODS

We searched four Chinese databases (SinoMed, CNKI, Wanfang and VIP) and four international databases (Cochrane Library, Embase, PubMed and Web of Science) for SRs of acupuncture for neurodegenerative diseases. The search period ran from the beginning of the database to March 5, 2023. Literature screening and data extraction were performed independently by two individuals. Methodological quality, risk of bias and associated evidence levels were assessed for all SRs using AMSTER 2, ROBIS and GRADE tools. In addition, the RCT overlap between SRs was calculated by corrected coverage area (CCA). We also conducted quantitative synthesis or descriptive analysis of the relevant data.

RESULTS

Finally, we identified 53 SRs (three were qualitative descriptions and fifty were meta-analyses). Under AMSTAR 2, only one SR was rated as moderate quality, six SRs as low quality and 46 SRs as very low quality. According to ROBIS, 33 SRs were rated as a high risk of bias and 20 as a low risk of bias. Cognitive functions in neurodegenerative diseases, activities of daily living and the motor and non-motor outcomes associated with PD were included to summary description. The pooled results show that acupuncture combined with conventional treatment may have an overall advantage over conventional treatment, but the quality of evidence is low. Specific adverse reactions/events were reported in 20 SRs. Common needle-related adverse events included pain, dizziness, bleeding, or subcutaneous hematoma. No severe adverse events were reported in any SRs.

CONCLUSION

Evidence suggests that acupuncture is generally effective and relatively safe for cognitive function and activities of daily living in neurodegenerative diseases. In addition, acupuncture may have some benefits in improving motor and non-motor symptoms in patients with PD. However, high-quality RCTs and SRs are still needed to further clarify the efficacy and safety of acupuncture in treating neurodegenerative diseases.

Electroacupuncture Pretreatment Attenuates Learning Memory Impairment Induced by Repeated Propofol Exposure and Modulates Hippocampal Synaptic Plasticity in Rats

Background

Recurrent propofol anesthesia in the peak of neurodevelopment may lead to learning-memory decline. This study aimed to examine the efficacy of electroacupuncture pretreatment in ameliorating the aforementioned learning memory deficits and to explore its underlying mechanisms in a rat model of repeated propofol exposure.

Methods

10-day-old Sprague Dawley rats were randomly assigned to five groups: the control, fat emulsion, propofol, electroacupuncture pretreatment and electroacupuncture pretreatment combined with propofol groups. The electroacupuncture pretreatment involved three consecutive daily sessions, while propofol was received intraperitoneally once daily for five days. Following the modeling period, the rats' learning-memory performance was assessed using the New Novel Arm Y-maze, New Object Recognition, and Morris Water Maze. The Nissl staining method was used to observe the development of hippocampal neurons, while Golgi staining was employed to observe hippocampal synaptic development.

Results

The electroacupuncture pretreatment significantly attenuated the learning and memory impairment induced by recurring propofol exposure in rats. Additionally, it facilitated the development of hippocampal neurons and synaptic plasticity in the hippocampus. Immunofluorescence and Western Blot analyses were conducted to detect the expression of proteins related to apoptosis, learning memory, and synaptic plasticity. In the propofol group, the pro-apoptotic factors Caspase-3 and Bax was up-regulated, while the anti-apoptotic factor Bcl-2 was down-regulated, as compared to the blank group. Additionally, the phosphorylated cAMP-response element binding protein (pCREB), brain-derived neurotrophic factor (BDNF), synaptophysin, and growth associated protein-43 (GAP-43) was significantly decreased. In contrast, the electroacupuncture pretreatment combined with propofol group exhibited decreased the Caspase-3 and Bax and increased the Bcl-2, as compared to the propofol group, meanwhile, the pCREB, BDNF, Synaptophysin and GAP-43 was increased.

Conclusion

Our findings indicate that electroacupuncture pretreatment can alleviate the learning and memory impairment induced by recurring propofol exposure in rats. This is achieved by enhancing hippocampal synaptic plasticity, activating the pCREB/BDNF pathway and inhibiting neuronal apoptosis.

Acupoint stimulation for long COVID: A promising intervention:

"Long COVID" is a sustained symptom following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to recent statistics, at least 65 million people have long COVID, which poses a long-term threat to human health. The pathogenic mechanisms of coronavirus disease 2019 (COVID-19) are complex and affect multiple organs and systems. Common symptoms include palpitations, breathing difficulties, attention and memory deficits, fatigue, anxiety, and depression. It is difficult to achieve satisfactory treatment effect with a single intervention. Currently, treatment strategies for long COVID are still in the exploratory stage, and there is an urgent need to find appropriate and effective methods for long COVID treatment. Traditional Chinese medicine is effective in treating the various phases of COVID-19. Previous studies have shown that acupoint stimulation therapy is effective in improving palpitations, dyspnea, cognitive impairment, anxiety, depression, and other symptoms in patients. According to previous studies, acupoint stimulation may improve various symptoms related to long COVID. This paper discusses the potential application value of acupoint stimulation in the treatment of long COVID-related symptoms, based on the common sequelae of various systems involved in long COVID, and the effect of acupoint stimulation in the treatment of similar symptoms and diseases in recent years.

The neuroprotective and neural circuit mechanisms of acupoint stimulation for cognitive impairment

Cognitive impairment is a prevalent neurological disorder that burdens families and the healthcare system. Current conventional therapies for cognitive impairment, such as cholinesterase inhibitors and N-methyl-d-aspartate receptor antagonists, are unable to completely stop or reverse the progression of the disease. Also, these medicines may cause serious problems with the digestive system, cardiovascular system, and sleep. Clinically, stimulation of acupoints has the potential to ameliorate the common symptoms of a variety of cognitive disorders, such as memory deficit, language dysfunction, executive dysfunction, reduced ability to live independently, etc. There are common acupoint stimulation mechanisms for treating various types of cognitive impairment, but few systematic analyses of the underlying mechanisms in this domain have been performed. This study comprehensively reviewed the basic research from the last 20 years and found that acupoint stimulation can effectively improve the spatial learning and memory of animals. The common mechanism may be that acupoint stimulation protects hippocampal neurons by preventing apoptosis and scavenging toxic proteins. Additionally, acupoint stimulation has antioxidant and anti-inflammatory effects, promoting neural regeneration, regulating synaptic plasticity, and normalizing neural circuits by restoring brain functional activity and connectivity. Acupoint stimulation also inhibits the production of amyloid β-peptide and the phosphorylation of Tau protein, suggesting that it may protect neurons by promoting correct protein folding and regulating the degradation of toxic proteins via the autophagy-lysosomal pathway. However, the benefits of acupoint stimulation still need to be further explored in more high-quality studies in the future.

Research Hotspots and Trends on Acupuncture for Anti-Inflammation: A Bibliometric Analysis from 2011 to 2021

Purpose

We here explored the research status, research hotspots, and development trend of acupuncture against inflammation from both quantitative and qualitative aspects through bibliometrics.

Methods

We used CiteSpace and VOSviewer to analyze the literature about acupuncture against inflammation from 2011 to 2021 in the Web of Science Core Collection database by using a visual knowledge map.

Results

In total, 1479 articles were included, and the number of articles published each year exhibited an upward trend. The largest number of articles were published in China (661), followed by the United States (287) and South Korea (164). The most productive institution is Beijing University of Chinese Medicine (72), while the most influential institution is the Capital Medical University (0.28). Evidence-based Complementary and Alternative Medicine (131) is the journal that published most articles on the topic. Lin Yiwen is the most prolific author, and Borovikova L is the most influential co-cited author. The keywords that have burst in the last 2 years are inflammation and activation. The keywords with the highest frequency of use are electroacupuncture (EA), inflammation, and expression.

Conclusion

The number of publications on acupuncture for anti-inflammation research is rapidly increasing. China is a productive country, but the influence of centrality is poor. Research institutions are concentrated in universities, and the whole collaborative network needs to be strengthened. The anti-inflammatory mechanism of acupuncture is the main focus of research in this field. Regulation of immune cell balance by acupuncture may be a hot topic in mechanism research. At present, immune cells, vagus nerve, signal pathway, inflammatory corpuscles, cytokines and neurotransmitters are popular research topics. In the future, the basic research of acupuncture for anti-inflammation transformed into clinical practice may be a trend. EA and bee venom acupuncture may be promising research directions for acupuncture treatment for inflammatory diseases.

Use of Acupuncture for Adult Health Conditions, 2013 to 2021: A Systematic Review

IMPORTANCE

Acupuncture is a popular treatment that has been advocated for dozens of adult health conditions and has a vast evidence base.

OBJECTIVE

To map the systematic reviews, conclusions, and certainty or quality of evidence for outcomes of acupuncture as a treatment for adult health conditions.

EVIDENCE REVIEW

Computerized search of PubMed and 4 other databases from 2013 to 2021. Systematic reviews of acupuncture (whole body, auricular, or electroacupuncture) for adult health conditions that formally rated the certainty, quality, or strength of evidence for conclusions. Studies of acupressure, fire acupuncture, laser acupuncture, or traditional Chinese medicine without mention of acupuncture were excluded. Health condition, number of included studies, type of acupuncture, type of comparison group, conclusions, and certainty or quality of evidence. Reviews with at least 1 conclusion rated as high-certainty evidence, reviews with at least 1 conclusion rated as moderate-certainty evidence, and reviews with all conclusions rated as low- or very low-certainty evidence; full list of all conclusions and certainty of evidence.

FINDINGS

A total of 434 systematic reviews of acupuncture for adult health conditions were found; of these, 127 reviews used a formal method to rate certainty or quality of evidence of their conclusions, and 82 reviews were mapped, covering 56 health conditions. Across these, there were 4 conclusions that were rated as high-certainty evidence, and 31 conclusions that were rated as moderate-certainty evidence. All remaining conclusions (>60) were rated as low- or very low-certainty evidence. Approximately 10% of conclusions rated as high or moderate-certainty were that acupuncture was no better than the comparator treatment, and approximately 75% of high- or moderate-certainty evidence conclusions were about acupuncture compared with a sham or no treatment.

CONCLUSIONS AND RELEVANCE

Despite a vast number of randomized trials, systematic reviews of acupuncture for adult health conditions have rated only a minority of conclusions as high- or moderate-certainty evidence, and most of these were about comparisons with sham treatment or had conclusions of no benefit of acupuncture. Conclusions with moderate or high-certainty evidence that acupuncture is superior to other active therapies were rare.

Clinical efficacy of acupuncture combined with Western medicine in the treatment of mild to moderate Alzheimer disease: A protocol of a randomized controlled trial

BACKGROUND

Alzheimer disease (AD) is a common cause of dementia, and there are still a lack of treatment options to reverse or prevent disease progression. Existing evidence shows that acupuncture has advantages in the treatment of AD, but whether the efficacy of acupuncture belongs to the placebo effect remains controversial, and there is no strict placebo-controlled clinical study to evaluate the efficacy and safety of acupuncture combined with Western medicine in the treatment of AD.

METHODS

This is a prospective randomized, a single-blind, sham-acupuncture controlled trial to study the clinical efficacy of acupuncture combined with Western medicine in the treatment of mild to moderate AD. Participants will be randomly divided into treatment and control groups. The treatment group using acupuncture combined with donepezil hydrochloride orally, and the control group using sham acupuncture combined with donepezil hydrochloride orally, followed up for 24 weeks after 24 weeks of continuous treatment. Outcome measures included: AD assessment scale-cognitive subscale, mini-mental state examination, activities of daily living, neuropsychiatric inventory questionnaire, serum superoxide dismutase, and homocysteine levels. Finally, SPASS 21.0 software was used for statistical analysis of the data.

DISCUSSION

This study will evaluate the efficacy of acupuncture combined with Western medicine in improving cognitive function and activities of daily living in AD patients. The results of this study will verify whether the efficacy of acupuncture in the treatment of AD belongs to the placebo effect, which will also provide a reference for the clinical use of acupuncture combined with Western medicine in the treatment of AD.

TRIAL REGISTRATION

The TCTR identification number is TCTR20220817004.

Electroacupuncture Stimulation Suppresses Postoperative Inflammatory Response and Hippocampal Neuronal Injury

Postoperative cognitive dysfunction (POCD) is consequence of anesthesia and surgery that primarily affects older people. The prevention and treatment of POCD has drawn an increasing attention in recent decades. Here, we established the animal model mimicked POCD after femoral fracture surgery, and analyze the effect of acupuncture stimulation on postoperative cognitive function after femoral fracture surgery. Compared with the mock group, the cognitive function performance was significantly decreased both in the anaesthesia group and the surgery group, between which the symptoms were more severe in the surgery group. The peripheral inflammation response and the neuron impairment and inflammation response in the hippocampus were observed in the surgery group, but only peripheral inflammation response was detected in the anaesthesia group. These findings indicated the POCD was the synergistic outcome of anaesthesia and surgical stimulation but with different pathogenic mechanism. The surgery with mental tri-needles (surgery+MTN) group outperformed the surgery group in terms of cognitive function performance. The peripheral inflammation response and the neuron impairment and inflammation response in the hippocampus was significantly reduced by the electroacupuncture stimulation. Our findings indicated the protection of electroacupuncture form POCD after femoral fracture surgery is related to the inhibition of inflammation response and neuron impairment.

Acupuncture for Mild Cognitive Impairment and Dementia: An Overview of Systematic Reviews

Background: Dementia is a gradual decline in cognitive ability and is becoming more common in our elderly population. Mild cognitive impairment (MCI) is defined as a slight clinical deterioration of memory capacity, below the level of normal aging, but does not constitute a clinical diagnosis of dementia. To date, no interventions have been proven to cure MCI and dementia fully. Purpose: To evaluate the potential effectiveness and safety of acupuncture for mild cognitive impairment (MCI) and dementia and evaluate the methodological quality of systematic reviews (SRs). Methods: We conducted a literature search for SRs with meta-analyses in seven Chinese and international databases through October 1, 2020. The basic characteristics of the included SRs/meta-analyses and the basic information of the original included randomized controlled trials were extracted by three reviewers independently. A meta-analysis of the original randomized controlled trials from the included SRs/meta-analyses was performed using Stata 12.0 software. The Assessing the Methodological Quality of Systematic Reviews 2 was used to assess the methodological quality of the included SRs/meta-analyses, and the Grading of Recommendations, Assessment, Development, and Evaluation was used to rate the quality of evidence. Results: A total of 35 SRs/meta-analyses were included, and the majority showed that acupuncture was more effective than western medicine or conventional therapy for MCI and dementia [odds ratio =1.39; 95% confidence interval (CI): 1.24, 1.56]. There was a statistically significant difference in the Mini-Mental State Examination score (weighted mean difference = 1.23; 95% CI: 0.78, 1.68; p < 0.00001), and there was no significant improvement in the activities of daily living score (weighted mean difference = 1.58; 95% CI: -0.02, 3.18; p = 0.053). The assessment results of Assessing the Methodological Quality of Systematic Reviews 2 showed that the methodological quality of most included SRs/meta-analyses was critically low; the lowest scores were items 2, 7, and 10. For Grading of Recommendations, Assessment, Development, and Evaluation, of the 73 outcomes, 50 (68.5%) outcomes were low or very low quality, and 23 (31.5%) outcomes were moderate quality. Conclusions: Acupuncture can be considered as an alternative for the treatment of MCI and dementia when western medicine or other therapies are contraindicated. More high-quality evidence is needed to determine further the effectiveness of acupuncture.

Electroacupuncture Pretreatment Ameliorates Anesthesia and Surgery-Induced Cognitive Dysfunction via Activation of an α7-nAChR Signal in Aged Rats

OBJECTIVE

Postoperative cognitive dysfunction (POCD) after anesthesia and surgery (AS) is a common complication in the elderly population. A cholinergic-dependent signal, the alpha7-nicotinic acetylcholine receptor (α7-nAChR), has been suggested to regulate cognitive processes in a variety of neurologic diseases. In the current study, we determined whether electroacupuncture (EA) pretreatment ameliorates AS-induced POCD in aged rats, as well as the underlying mechanism.

METHODS

Male Sprague-Dawley rats (20 months old) were randomly assigned to the following 5 groups (n=12): vehicle; POCD (tibial fracture surgery); EA plus POCD; EA plus POCD and alpha-bungarotoxin (α-BGT); and POCD plus α-BGT groups. Alpha-bungarotoxin (1 μg/kg), a selective antagonist of α7-nAChR, was administrated via intraperitoneal injection before EA. Thirty days post-AS, the Morris water maze and a novel objective recognition test were used to evaluate cognitive function. Neuronal amount, apoptosis, microglial activation, percentage of high mobility group box 1 (HMGB1)- and nuclear factor-κB (NF-κB)-positive microglia, and levels of HMGB-1 downstream factors, including NF-κB, interleukin-6 (IL-6), and IL-1β, were detected by Nissl staining, immunofluorescence, and Western blot assays.

RESULTS

EA pretreatment significantly increased crossing platform times and elevated the time with a novel object, restored the quantity of neurons, decreased TUNEL-positive neurons, alleviated activation of microglia, downregulated expression of HMGB1 and NF-κB in the microglia, and reduced levels of phosphor-NF-κB, IL-6, and IL-1β 35 days after AS, while α-BGT partially reversed these changes.

CONCLUSION

EA pretreatment improved AS-induced POCD in aged rats, and the underlying mechanism may be associated with inhibition of HMGB1-NF-κB via an α7-nAChR signal in the microglia.